Answer:
3.12years
Explanation:
Given the average salary (in thousands of dollars) at a certain company for the first ten years of its existence approximated by the model
S = 0.2t² + 2.1t + 32.5,
To calculate the years it take for the average salary to reach $41,000, we will substitute s = 41000 and calculate for t
41 = 0.2t² + 2.1t + 32.5
Multiply through by 10
410 = 2t²+21t+325
2t²+21t+325 = 410
2t²+21t+325-410= 0
2t²+21t-85 = 0
On factorizing:
t = -21±√21²-4(2)(-85)/2(2)
t = -21±√441+680/4
t = -21±√1121/4
t = -21+33.48/4
t = 12.48/4
t = 3.12
Hence the number of years to average hundredth of a year is 3.12years